The present invention relates to a piling and drilling rig having a leader, a deflection apparatus for the deflection of a rope which is pivotally connected to the head of the leader in a manner pivotable between at least one transport position and at least one working position.
Generic piling and drilling rigs are in particular used in special underground engineering applications. Such rigs essentially comprise the so-called load bearing structure and the mast or leader with a rotary drive and Kelly bar. Piped or unpiped bores can be carried out in the ground with the help of these rigs and the ground material which accumulates can be brought to the surface. In particular in rigs which are used in special underground engineering, the mast or leader frequently has a substantial height, with a deflection apparatus being arranged at its upper end which has the underlying object of deflecting the hoist rope of the piling and drilling rig in the direction of the piling or drilling axis in front of the leader or mast.
The mast or leader is moved from an almost vertical working position into a horizontal position in which the leader or mast is supported on the load bearing structure itself to facilitate the transport of the total construction apparatus. A small transport height is required in the horizontal transport position; that is, everything which projects beyond the permitted transport height has to be brought below this level by suitable measures. A transport length of the rig which is as short as possible has importance in addition to the aspect of the transport height, in particular with tight road conditions. The transport height or transport length of the rig is furthermore increased again by the deflection apparatus arranged at the head of the mast or leader in a manner directed to project obliquely upward in a transport position.
To optimize the transport height with respect to the deflection apparatus, the deflection apparatus is currently folded rearwardly below the permitted transported height with practically all commercial piling and drilling rigs.
A piece of instruction apparatus is known from EP 1 655 415 A1 at whose mast head a deflection device is arranged having a first, front deflection pulley and a second rear deflection pulley. To achieve the permitted transport height, the front deflection pulley can be pivoted about an axis transverse to the longitudinal axis of the mast behind the second deflection pulley.
A similar apparatus is known from DE 101 23 403 B4 in which a mast head is pivotably arranged at the upper end of the mast which can be pivoted from a working position into a transport position. In this respect, the mast head is likewise pivoted about an axis disposed transversely to the direction of extent of the mast from a position contacting the mast almost at a right angle into a position directed lengthways with respect to the mast. The same applies to the working apparatus of specification U.S. Pat. No. 5,269,107.
It is disadvantageous in the construction apparatus of specifications EP 1 655 415 A1, U.S. Pat. No. 5,269,107 and DE 101 23 403 B4 that the transport length increases by a not insubstantial part by the folding of the deflection apparatus/mast head.
In order likewise to reduce the transport length, rigs are known which can fold the upper part of the leader horizontally to the front in a separate, second step in order thereby to reduce the transport length. This procedure is, however, associated with a high time and installation effort since the mast head has to be released at a further screw connection or bolt connection to be able to fold it forward accordingly.
There is still a further possibility, in particular with piling and drilling rigs having a leader rotating device, in which the total leader or mast is rotated by 90° about a longitudinal axis in the horizontal transport position so that the deflection apparatus comes to lie beneath the transport height.
However, none of these approaches shows a satisfactory design in which a transport length is achieved which is as short as possible and the permitted transport height is observed. Since the erection and laying down of the mast or leader and the associated folding of the deflection apparatus is an action which is repeated regularly, this procedure should be able to be effected relatively easily and fast under construction site conditions; if possible it should be able to be carried out without any additional means.